Multilayer PCB Warpage Simulation for Reflow Welding Yield

The patent performs warpage simulation and prediction before the actual reflow welding process. By calculating the warpage level of each region in the multi-layer circuit board based on warpage data of individual layers and a stacked state model, the system identifies high-risk regions in advance. This preliminary action allows for preventive measures to be taken, such as adjusting welding parameters or reinforcing specific areas, thereby preventing warpage-related defects and improving yield while maintaining the multi-layer stacking configuration.

The patent creates a virtual copy or model of the multi-layer circuit board's warpage behavior through simulation. Instead of relying solely on physical measurement after welding, the system generates a warpage level map that replicates the expected deformation patterns based on input warpage data from each layer. This virtual model allows for non-intrusive, timely detection of potential defects before they manifest as actual yield losses, while maintaining operational simplicity through automated calculation.

The patent divides the multi-layer circuit board into individual layers, each with its own warpage data characteristics. By segmenting the overall warpage prediction task into layer-specific calculations and then combining them according to the stacked state, the system achieves region-level warpage prediction accuracy. The segmentation allows for manageable processing of each layer's data independently, reducing the overall computational complexity compared to treating the entire multi-layer structure as a single unit.